This is a recipe I come back to time and time again — when I’m hosting, during the holidays, when I’m just craving a hearty breakfast. I always use the same base recipe, I just switch up the ingredients based on what’s in the fridge. It’s such a great way to get rid of things about to go bad!

This iteration has mushrooms + green pepper + white onion all sautéed in butter. Honestly, it’s my mom’s bread in the bottom that makes this. Sadly her recipe is a family secret, but choose whatever your personal favorite bread is and go for it!

SIMPLE BREAKFAST CASSEROLE INGREDIENTS:

BASE:

• Eggs
• Milk
• Kosher salt
• Freshly ground black pepper
• 2-3 slices of bread
• Butter 

CUSTOMIZABLE TOPPINGS:

• Breakfast sausage or bacon
• Diced mushrooms
• Diced onion
• Diced bell pepper of your choice
• Cheese (cheddar, feta, mozzarella, Swiss, Gruyère — whatever you want/have!)

HOW TO MAKE MY SIMPLE BREAKFAST CASSEROLE:

• STEP 1: Spray a 9×13-inch casserole dish with nonstick spray (I used coconut oil spray).
• STEP 2: Sauté the sausage, diced onion, mushrooms, and peppers (or whatever toppings you are using) in the butter until nice and caramelized.
• STEP 3: Whisk together eggs, milk, and S&P.
• STEP 4: Tear the bread into pieces and use it to line the bottom of a casserole dish.
• STEP 5: Add the sausage, peppers, mushrooms, onion (or your toppings of choice), and cheese.
• STEP 6: Pour the egg mixture over the top.
• STEP 7: Cover and leave in fridge till ready to bake (I like the assemble it the night before I plan to cook it and refrigerate it overnight).
• STEP 8: Bake uncovered at 375°F for 45 minutes (or check to make sure the middle is set and no longer runny).
• STEP 9: Call it DONE and serve!

NOTES, SUBS, AND ADDITIONS:

• This casserole reheats great in the microwave to enjoy all week!
• It’s also freezer friendly. You can assemble it up to the point where you refrigerate it overnight. Instead of refrigerating it, wrap it tightly with plastic wrap followed by foil and store in the freezer for up to 2 months. Let it thaw in the refrigerator overnight, then bake it per recipe instructions.
• Add or swap out whatever veggies you’d like. Good options would be diced bell peppers (red, orange, or yellow), zucchini, squash, potato, broccoli, or chopped spinach. Sauté them first like you would the mushrooms, onion, and pepper.
• In terms of meat, bacon, sausage, pancetta, or finely diced ham would all be great.
• To make it vegetarian, skip the meat and add more mushrooms. You may want to add more butter or some olive oil to the pan when sautéing the veggies, since you won’t have the extra grease from the meat.
• To make it gluten-free, use a GF bread.
• To make it dairy-free, use a DF milk alternative, use oil in lieu of butter, and skip the cheese.

Simple Breakfast Casserole

Recipe by KateCourse: Breakfast

This is a recipe I come back to time and time again — when I’m hosting, during the holidays, or when I’m just craving a hearty breakfast. This recipe includes “base” ingredients that I always keep the same, as well as a toppings combination that I love. I’m including these toppings so you can see how and when they’re prepared, but know that they are completely customizable based on what you’re in the mood for and/or have in the fridge.

Ingredients

• 1 tablespoon butter

• Approximately 1 pound breakfast sausage or bacon (if using bacon, chop it up before adding it to the skillet)

• 1/2 white (or yellow or red) onion, diced

• Approximately 1 cup diced mushrooms

• 1 bell pepper, diced

• 9 eggs

• 2 cups milk

• 1 teaspoon kosher salt

• 1/2 teaspoon pepper

• 2-3 slices of bread, torn or cut into roughly 1/2-inch cubes/pieces

• 1.5 cups shredded cheese of your choice

Directions

• Spray a 9×13-inch casserole dish with nonstick spray (I used coconut oil spray).
• Melt butter in a large skillet over medium heat. Sauté the sausage, onion, mushrooms, and peppers (or whatever veggies you are using) in the butter until all the veggies are nice and caramelized and the meat is cooked through.
• In a large bowl, whisk together the eggs, milk, and S&P.
• Tear the bread into pieces and use it to line the bottom of the prepared casserole dish.
• On top of the bread, add the cooked sausage, peppers, mushrooms, and onion (or your toppings of choice), and cheese.
• Pour the egg mixture over top.
• Cover the dish and leave it in the fridge until you’re ready to bake (I like to assemble it the night before and refrigerate overnight).
• When you’re ready to cook the casserole, heat oven to 375°F.
• Bake uncovered for 45 minutes or until the middle is set and no longer runny.

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